Spring core for a mattress

ABSTRACT

A spring core is provided that includes a head portion, a foot portion, and a middle portion positioned between the head portion and the foot portion. The head portion and the foot portion each include a plurality of coil springs arranged in a matrix with each coil spring of the head portion and foot portion having a first height and a second height, respectively. The middle portion also includes a plurality of coil springs arranged in a matrix, but with each coil spring of the middle portion having a third height and with the middle portion providing greater support, less motion transfer, or both greater support and less motion transfer than the head portion and the foot portion.

TECHNICAL FIELD

The present invention relates to spring cores. In particular, the present invention includes spring cores that have multiple zones, which each provide different levels of support, motion transfer, or both support and motion transfer.

BACKGROUND

Spring cores are typically made of either a plurality of coil springs interconnected into a single unit or pocketed coil springs, which are also known as wrapped coils, encased coils, encased springs, or Marshall coils. Pocketed coil springs are generally recognized as providing a unique feel to a mattress when used in the spring core because each discrete coil is capable of moving independently to support the body of a user, or a portion thereof, resting on the mattress. In particular, in pocket coil spring assemblies, each coil is wrapped in a fabric pocket and move s substantially independently of the other coils in the pocket coil spring assembly to thereby provide individualized comfort and contouring to the body of a user. Moreover, as a result of moving substantially independently from one another, the pocket coils also do not directly transfer motion from one pocket coil to another, such that the movement of one user resting on a mattress assembly using pocket coils will not disturb another user resting on the mattress assembly. In this regard, mattress assemblies constructed with pocketed coil springs are generally recognized as providing a soft and luxurious feel, and are often more desirable than a traditional interconnected coil spring mattress. Accordingly, a spring core that includes pocketed coil spring assemblies and further improves upon the support and feel provided by traditional pocketed coil spring assemblies would be both highly desirable and beneficial.

SUMMARY

The present invention includes spring cores. In particular, the present invention includes spring cores that have multiple zones, which each provide different levels of support, motion transfer, or both support and motion transfer.

In one exemplary embodiment of the present invention, a spring core is provided that includes a head portion, a foot portion, and a middle portion positioned between the head portion and the foot portion. The head portion includes a plurality of coil springs arranged in a matrix. The foot portion also includes a plurality of coil springs arranged in a matrix. Similar to the head portion and the foot portion, the middle portion additionally includes a plurality of coil springs arranged in a matrix, but unlike the plurality of coil springs of the head portion and the foot portion, each of the coil springs of the middle portion is surrounded by a flexible enclosure.

With respect to the coil springs of the exemplary spring core, the plurality of coil springs of the head portion have a first height, the plurality of coil springs of the foot portion have a second height that is substantially the same as the first height of the coil springs of the head portion, and the plurality of coil springs of the middle portion have a third height that is substantially the same as the first height of the coil springs of the head portion as well as the second height of the coil springs of the foot portion.

With respect to the flexible enclosure surrounding each of the plurality of coil springs of the middle portion, the flexible enclosure is generally a cylindrical (or tubular) fabric pocket that completely encloses the respective coil spring. In this regard, the flexible enclosure is preferably made of an inelastic fabric which can be joined or welded together by heat and pressure (e.g., via ultrasonic welding or by a similar thermal welding procedure) to form such a cylindrical structure. For example, suitable fabrics that can be used for the flexible enclosure can include one of various thermoplastic fibers known in the art, such as non-woven polymer-based fabric, non-woven polypropylene material, or non-woven polyester material. Furthermore, the flexible enclosure surrounding each of the plurality of coil springs of the middle portion is connected to the flexible enclosure of an adjacent one of the plurality of coil springs of the middle portion. The connection between the flexible enclosures allows each of the plurality of coil springs of the middle portion to partially compress independently of an adjacent one of the plurality of coil springs of the middle portion. As such, the middle portion exhibits a small amount of motion transfer across the middle portion as compared to the head portion and the foot portion of the spring core resulting in a softer feel that conforms more to the portion of a user's body positioned on the middle portion of the spring core.

In a second exemplary embodiment of the present invention, a spring core is provided that also includes a head portion, a foot portion, and a middle portion positioned between the head portion and the foot portion. The head portion includes a plurality of coil springs arranged in a matrix as well as a flexible enclosure that surrounds each of the plurality of coil springs of the head portion. The middle portion similarly includes a plurality of coil springs arranged in a matrix as well as a flexible enclosure that surrounds each of the plurality of coil springs of the middle portion, and the foot portion also includes a plurality of coil springs arranged in a matrix as well as a flexible enclosure that surrounds each of the plurality of coil springs of the foot portion. Moreover, with respect to the coil springs of the second exemplary spring core, the plurality of coil springs of the head portion all have a first height, the plurality of coil springs of the foot portion have a second height that is substantially the same as the first height of the coil springs of the head portion, and the plurality of coil springs of the middle portion have a third height that is greater than the first height of the coil springs of the head portion as well as the second height of the coil springs of the foot portion. In this regard, due to the greater height of the coil springs of the middle portion, the middle portion of the spring core provides a greater level of support as compared to the head portion and the foot portion. Furthermore, because springs are typically more durable than foam and do not lose height as quickly or as severely over time, the greater initial height of the coil springs of the middle portion results in the spring core preventing the formation of a permanent indentation in the center of a mattress as is typically seen in foam mattresses.

In a third exemplary embodiment of the present invention, a spring core is provided that also includes a head portion, a foot portion, and a middle portion positioned between the head portion and the foot portion. The head portion includes a plurality of coil springs arranged in a matrix as well as a flexible enclosure that surrounds each of the plurality of coil springs of the head portion. The middle portion similarly includes a plurality of coil springs arranged in a matrix as well as a flexible enclosure that surrounds each of the plurality of coil springs of the middle portion. The foot portion also includes a plurality of coil springs arranged in a matrix as well as a flexible enclosure that surrounds each of the plurality of coil springs of the foot portion. In this third exemplary spring core, the matrix of the middle portion defines one or more spaces and the middle portion of the spring core further includes one or more interstitial springs positioned within a respective one of the spaces.

With further respect to the coil springs of the third exemplary spring core, the plurality of coil springs of the head portion all have a first height, the plurality of coil springs of the foot portion have a second height that is substantially the same as the first height of the coil springs of the head portion, and the plurality of coil springs of the middle portion have a third height that is substantially the same as the first height of the coil springs of the head portion and the second height of the coil springs of the foot portion. The interstitial springs positioned within the spaces of the middle portion then each have a height that is greater than the third height of the coil springs of the middle portion or, in certain embodiments, the height of the interstitial spring is substantially the same as the height of the coil springs of the middle portion. Regardless of the particular configuration and height of the interstitial springs, however, the inclusion of the interstitial springs in the middle portion increases the spring density within the middle portion such that the middle portion of the spring core provides a greater level of support as compared to the head portion and the foot portion.

Further features and advantages of the present invention will become evident to those of ordinary skill in the art after a study of the description, figures, and non-limiting examples in this document.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary spring core for a mattress made in accordance with the present invention;

FIG. 2 is a perspective view of another exemplary spring core for a mattress made in accordance with the present invention;

FIG. 3 is a perspective view of another exemplary spring core for a mattress made in accordance with the present invention; and

FIG. 4 is a partial sectional view of the spring core of FIG. 3 taken along the line 4-4 shown in FIG. 3.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

The present invention includes spring cores. In particular, the present invention includes spring cores that have multiple zones, which each provide different levels of support, motion transfer, or both support and motion transfer.

Referring first to FIG. 1, in one exemplary embodiment of the present invention, a spring core 10 is provided that includes a head portion 20, a foot portion 40, and a middle portion 30 positioned between the head portion 20 and the foot portion 40. The head portion 20 includes a plurality of coil springs 22 arranged in a matrix as well as one or more helical wires 26 connecting each one of the plurality of coil springs 22 of the head portion 20 to an adjacent one of the plurality of coil springs 22 of the head portion 20, as further discussed below. The foot portion 40 similarly includes a plurality of coil springs 42 arranged in a matrix as well as one or more helical wires 46 connecting each one of the plurality of coil springs 42 of the foot portion 40 to an adjacent one of the plurality of coil springs 42 of the foot portion 40. Similar to the head portion 20 and the foot portion 40, the middle portion 30 also includes a plurality of coil springs 32 arranged in a matrix, but unlike the plurality of coil springs 22, 42 of the head portion 20 and the foot portion 40, each of the coil springs 32 of the middle portion 30 is surrounded by a flexible enclosure 34, as also further discussed below. In the exemplary embodiment shown in FIG. 1, a border wire 12 also extends around the upper perimeter of the spring core 10 such that the head portion 20, the middle portion 30, and the foot portion 40 are all contained within the border wire 12.

With respect to the coil springs of the exemplary spring core 10 shown in FIG. 1, the plurality of coil springs 22 of the head portion 20 are made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 22 to an upper end convolution opposite the lower end convolution with each of the coil springs 22 of the head portion 20 having a first height extending between the lower end convolution and the upper end convolution. The plurality of coil springs 42 of the foot portion 40 are similarly made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 42 to an upper end convolution opposite the lower end convolution with each of the coil springs 42 of the foot portion 40 having a second height that extends between the lower end convolution and the upper end convolution and that is substantially the same as the first height of the coil springs 22 of the head portion 20. The plurality of coil springs 32 of the middle portion 30 are also made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 32 to an upper end convolution opposite the lower end convolution with each of the coil springs 32 of the middle portion 30 having a third height that extends between the lower end convolution and the upper end convolution and that is substantially the same as the first height of the coil springs 22 of the head portion 20 as well as the second height of the coil springs 42 of the foot portion 40. In the embodiment shown in FIG. 1, the first height of the coil springs 22 of the head portion 20, the second height of the coil springs 42 of the foot portion 40, and the third height of the coil springs 32 of the middle portion 30 are all about six to fourteen inches, but various other types of springs, such as coil springs having a different height, could also be used in an exemplary pocket coil spring assembly without departing from the spirit and scope of the present invention.

With respect to the helical wires 26 in the head portion 20 of the spring core 10, and as shown in FIG. 1, each helical wire 26 spirals horizontally across the entire width of the spring core 10 interlacing adjacent rows of coil springs 22 in the head portion 20 of the spring core 10. The helical wires 26 thus act to interconnect not only each coil spring 22 to the adjacent coil spring 22 within the same row, but also to the adjacent coil spring in an adjacent row. The helical wires 46 in the foot portion 40 of the spring core 10 similarly connect the plurality of coil springs 42 in the foot portion 40 of the spring core 10. Such an interconnected arrangement of the coil springs 22, 42 in the head portion 20 and the foot portion 40 results in an increased amount of motion transfer in the head portion 20 and the foot portion 40 of the spring core 10, as further discussed below.

With respect to the flexible enclosure 34 surrounding each of the plurality of coil springs 32 of the middle portion 30, in the exemplary spring core 10 shown in FIG. 1, the flexible enclosure 34 is generally a cylindrical (or tubular) fabric pocket that completely encloses the respective coil spring 32. In this regard, the flexible enclosure 34 is preferably made of an inelastic fabric which can be joined or welded together by heat and pressure (e.g., via ultrasonic welding or by a similar thermal welding procedure) to form such a cylindrical structure. For example, suitable fabrics that can be used for the flexible enclosure 34 can include one of various thermoplastic fibers known in the art, such as non-woven polymer-based fabric, non-woven polypropylene material, or non-woven polyester material. Furthermore, the flexible enclosure 34 surrounding each of the plurality of coil springs 32 of the middle portion 30 is connected to the flexible enclosure 34 of an adjacent one of the plurality of coil springs 32 of the middle portion 30. Although not expressly shown in FIG. 1, in this exemplary spring core 10 the flexible enclosures 34 are connected to each other by an ultrasonic weld that extends along the height of the flexible enclosure 34, or a substantial portion thereof. Other connections are also contemplated including, but not limited to, adhesives, hook and loop fasteners, snaps, buttons, or the like. In any event, the connection between the flexible enclosures 34 allows each of the plurality of coil springs 32 of the middle portion 30 to partially compress independently of an adjacent one of the plurality of coil springs 32 of the middle portion 30. As such, the middle portion 30 exhibits a small amount of motion transfer across the middle portion 30 as compared to the head portion 20 and the foot portion 40 of the spring core 10 resulting in a softer feel that conforms more to the portion of a user's body positioned on the middle portion 30 of the spring core 10.

With further respect to the flexible enclosures 34, by surrounding each of the coil springs 32 of the middle portion 30 with a flexible enclosure 34, it is possible to impart a desired level of pre-compression to the coil springs 32. As previously mentioned, the first height of each of the plurality of coil springs 22 of the head portion 20, the second height of each of the plurality of coil springs 42 of the foot portion 40, and the third height of each of the plurality of coil springs 32 of the middle portion 30 are substantially the same. However, it should be understood that in the exemplary embodiment shown in FIG. 1, the plurality of coil springs 32 of the middle portion 30 are pre-compressed within the flexible enclosures 34 and therefore the coil springs 32 have a resting height greater than the height of the coil springs 22 in the head portion 20 and the coil springs 42 in the foot portion 40. It is only the pre-compressed height (i.e., the third height) of the coil spring 32 within the flexible enclosure 34 that is equal to the first height of each of the plurality of coil springs 22 of the head portion 20 and the second height of each of the plurality of coil springs 42 of the foot portion 40. Through the use of such pre-compressed coil springs 32 in the middle portion 30, the middle portion 30 of the spring core 10 provides a greater level of support as compared to the head portion 20 and the foot portion 40. Of course, it is appreciated that the overall geometry of the coil springs 22, 32, 42 used in the head portion 20, middle portion 30, and/or foot portion 40 can also be readily varied to impart a particular feel or characteristic without departing from the spirit and scope of the present invention.

Referring now to FIG. 2, in another embodiment of the present invention, a spring core 110 is provided that, similar to the spring core 10 described above with reference to FIG. 1, includes a head portion 120, a foot portion 140, and a middle portion 130 positioned between the head portion 120 and the foot portion 140. The head portion 120 includes a plurality of coil springs 122 arranged in a matrix as well as a flexible enclosure 124 that surrounds each of the plurality of coil springs 122 of the head portion 120. The middle portion 130 similarly includes a plurality of coil springs 132 arranged in a matrix as well as a flexible enclosure 134 that surrounds each of the plurality of coil springs 132 of the middle portion 130. The foot portion 140 also includes a plurality of coil springs 142 arranged in a matrix as well as a flexible enclosure 144 that surrounds each of the plurality of coil springs 142 of the foot portion 140.

With respect to the coil springs of the exemplary spring core 110 shown in FIG. 2, the plurality of coil springs 122 of the head portion 120 are again made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 122 to an upper end convolution opposite the lower end convolution with each of the coil springs 122 of the head portion 120 having a first height extending between the lower end convolution and the upper end convolution. The plurality of coil springs 142 of the foot portion 140 are similarly made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 142 to an upper end convolution opposite the lower end convolution with each of the coil springs 142 of the foot portion 140 having a second height extending between the lower end convolution and the upper end convolution that is substantially the same as the first height of the coil springs 122 of the head portion 120. The plurality of coil springs 132 of the middle portion 130 are also similarly made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 132 to an upper end convolution opposite the lower end convolution; however, the coil springs 132 of the middle portion 130 have a third height extending between the lower end convolution and the upper end convolution of each of the coils springs 132 that is greater than the first height of the coil springs 122 of the head portion 120 as well as the second height of the coil springs 142 of the foot portion 140. As such, due to the greater height of the coil springs 132 of the middle portion 130, the middle portion 130 of the spring core 110 is configured to provide a greater level of support as compared to the head portion 120 and the foot portion 140. Moreover, and because springs are typically more durable than foam and do not lose height as quickly or as severely over time, the greater initial height of the coil springs 132 of the middle portion 130 results in the spring core 110 preventing the formation of a permanent indentation in the center of a mattress as is typically seen in foam mattresses. Furthermore, due to the initial greater height of the coil springs 132 of the middle portion 130, this is true even if the coil springs 132 in the middle portion do lose a certain amount of height over time.

With respect to the flexible enclosures 124, 134, 144 surrounding each of the plurality of coil springs 122, 132, 142 of the head portion 120, the middle portion 130, and the foot portion 140 in the exemplary spring core 110 shown in FIG. 2, each flexible enclosure 124, 134, 144 is substantially the same as the flexible enclosure 34 described above with reference to FIG. 1, and is connected by an ultrasonic weld to the flexible enclosure 124, 134, 144 surrounding an adjacent one of the plurality of coil springs 122, 132, 142. In this way, since all of the coil springs 122, 132, 142 are surrounded by a respective flexible enclosure 124, 134, 144, each of the coil springs 122, 132, 142 is able to partially compress independently of an adjacent one of the plurality of coil springs 122, 132, 142 and therefore the spring core 110 of FIG. 2 provides a small amount of motion transfer across the entirety of the spring core 110.

Referring now to FIGS. 3 and 4, in another embodiment of the present invention, a spring core 210 is provided that also includes a head portion 220, a foot portion 240, and a middle portion 230 positioned between the head portion 220 and the foot portion 240. The head portion 220 includes a plurality of coil springs 222 arranged in a matrix as well as a flexible enclosure 224 that surrounds each of the plurality of coil springs 222 of the head portion 220. The middle portion 230 similarly includes a plurality of coil springs 232 arranged in a matrix as well as a flexible enclosure 234 that surrounds each of the plurality of coil springs 232 of the middle portion 230, and the foot portion 240 also includes a plurality of coil springs 242 arranged in a matrix as well as a flexible enclosure 244 that surrounds each of the plurality of coil springs 242 of the foot portion 240. In the exemplary spring core 210 shown in FIGS. 3 and 4, the matrix of the middle portion 230 defines one or more spaces 236 and the middle portion 230 of the spring core 210 further includes one or more interstitial springs 238 positioned within a respective one of the spaces 236, as further discussed below.

With respect to the coil springs of the exemplary spring core 210 shown in FIG. 3, the plurality of coil springs 222 of the head portion 220 are made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 222 to an upper end convolution opposite the lower end convolution with each of the coil springs 222 of the head portion 220 having a first height extending between the lower end convolution and the upper end convolution. The plurality of coil springs 242 of the foot portion 240 are similarly made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 242 to an upper end convolution opposite the lower end convolution with each of the coil springs 242 of the foot portion 240 having a second height extending between the lower end convolution and the upper end convolution and that is substantially the same as the first height of the coil springs 222 of the head portion 220. The plurality of coil springs 232 of the middle portion 230 are also made of a continuous wire that helically spirals from a lower end convolution at one end of the coil spring 232 to an upper end convolution opposite the lower end convolution with each of the coil springs 232 of the middle portion 230 having a third height extending between the lower end convolution and the upper end convolution that is substantially the same as both the first height of the coil springs 222 of the head portion 220 and the second height of the coil springs 242 of the foot portion 240.

With respect to the flexible enclosures 224, 234, 244 surrounding each of the plurality of coil springs 222, 232, 242 of the head portion 220, the middle portion 230, and the foot portion 240 in the exemplary spring core 210 shown in FIGS. 3 and 4, each flexible enclosure 224, 234, 244 is substantially the same as the flexible enclosure 34 described above with reference to FIG. 1, and is connected by an ultrasonic weld to the flexible enclosure 224, 234, 244 surrounding an adjacent one of the plurality of coil springs 222, 232, 242. Since all of the coil springs 222, 232, 242 are surrounded by a respective flexible enclosure 224, 234, 244, each of the coil springs 222, 232, 242 is able to partially compress independently of an adjacent one of the plurality of coil springs 222, 232, 242 and therefore the spring core 210 of FIGS. 3 and 4 exhibits a small amount of motion transfer across the entirety of the spring core 210.

With further respect to the flexible enclosures 234 of the middle portion 230 of the spring core 210, and as mentioned above, a plurality of spaces 236 are defined in the middle portion 230. In particular, four adjacent flexible enclosures 234 that form a square define one of the spaces 236 between the four flexible enclosures 234. Of course, it should be understood that in other embodiments of the present invention the plurality of coil springs can be alternatively arranged, in which case the spaces would be defined by a different number of flexible enclosures. For example, in a triangular matrix where each row of coil springs is offset from the immediately adjacent row, the spaces would be defined by three adjacent flexible enclosures. In any event, and as shown in the partial sectional view of FIG. 4, the spaces 236 extend along the entire height of the flexible enclosures 234 with each space 236 in the middle portion 230 including an interstitial spring 238 positioned within the space 236 defined between the four adjacent flexible enclosures 234.

Referring now more specifically to FIG. 4 which shows a portion of the spring core 210 of FIG. 3 removed to better show the interstitial springs 238, each interstitial spring 238 is made of a continuous wire that helically spirals from a lower end convolution at one end of the interstitial spring 238 to an upper end convolution opposite the lower end convolution with each interstitial spring 238 similar to the coil springs 232 of the middle portion 230. However, the interstitial springs 238 have a height extending between the lower end convolution and the upper end convolution that is greater than the third height of the coil springs 232 of the middle portion 230. Furthermore, each of the one or more interstitial springs 238 has a diameter that is less that a diameter of each of the plurality of coil springs 232 of the middle portion 230.

As also shown in FIG. 4, the pitch between each of the convolutions of the interstitial spring 238 also varies as the continuous wire forming each interstitial spring 238 helically spirals from the lower end convolution to the upper end convolution. In this way, the interstitial spring 238 exhibits a variable loading response as the interstitial spring 238 is compressed. Of course, it is appreciated that the overall geometry of interstitial springs in the middle portion 230 can also be readily varied to impart a particular feel or characteristic without departing from the spirit and scope of the present invention. For example, in some other embodiments, the height of the interstitial spring can be substantially the same as the height of the coil springs 232 of the middle portion 230. Regardless of the particular configuration of the interstitial springs 238, however, the inclusion of the interstitial springs 238 to the middle portion 230 increases the spring density within the middle portion 230 such that the middle portion 230 of the spring core 210 provides a greater level of support as compared to the head portion 220 and the foot portion 240.

In each of the exemplary spring cores 10, 110, 210 described above, the middle portion 30, 130, 230 differs from a head portion 20, 120, 220 and a foot portion 40, 140, 240 that are substantially identical. It is contemplated, however, that different arrangements are also possible without departing from the spirit and scope of the present invention. For example, in contrast to the spring core 10 described above with reference to FIG. 1 where the middle portion 30 included flexible enclosures 34 surrounding the coil springs 32, in some embodiments, it is the head portion, the foot portion, or both the head portion and the foot portion that further includes a plurality of flexible enclosures that surround each of the plurality of coil springs and the plurality of coil springs in the middle portion are left uncovered and connected by one or more helical wires.

Similarly, in other embodiments the spring core can be characterized as including a first side portion (e.g., a left side) and a second side portion (e.g., a right side) opposite the first side portion, and the configuration of the first side portion can be different than the configuration of the second side portion much in the same way that the middle portion differed from the head and foot portions of the above described spring cores. In this way, it is the left or right side of the spring core that provides greater support, less motion transfer, or both greater support and less motion transfer as compared to the other side of the spring core. For example, in contrast to the spring core 10 described above with reference to FIG. 1, a right side of the spring core further includes a plurality of flexible enclosures that surround each of the plurality of coil springs and the plurality of coil springs in the left side of the spring core are left uncovered and connected by one or more helical wires.

One of ordinary skill in the art will recognize that additional embodiments are also possible without departing from the teachings of the present invention or the scope of the claims which follow. This detailed description, and particularly the specific details of the exemplary embodiments disclosed herein, is given primarily for clarity of understanding, and no unnecessary limitations are to be understood therefrom, for modifications will become apparent to those skilled in the art upon reading this disclosure and may be made without departing from the spirit or scope of the claimed invention. 

What is claimed is:
 1. A spring core comprising: a head portion including a plurality of coil springs arranged in a matrix with each coil spring of the head portion having a first height; a foot portion including a plurality of coil springs arranged in a matrix with each coil spring of the foot portion having a second height; and a middle portion positioned between the head portion and the foot portion, the middle portion including a plurality of coil springs arranged in a matrix with each coil spring of the middle portion having a third height, the middle portion providing greater support, less motion transfer, or both greater support and less motion transfer than the head portion and the foot portion.
 2. The spring core of claim 1, further comprising a flexible enclosure surrounding each of the plurality of coil springs of the middle portion.
 3. The spring core of claim 2, wherein the first height, the second height, and the third height are substantially the same.
 4. The spring core of claim 1, wherein each of the plurality of coil springs of the middle portion is configured to partially compress independently of an adjacent one of the plurality of coil springs of the middle portion.
 5. The spring core of claim 3, wherein the head portion further comprises one or more helical wires connecting each of the plurality of coil springs of the head portion to an adjacent one of the plurality of coil springs of the head portion; and wherein the foot portion further comprises one or more helical wires connecting each of the plurality of coil springs of the foot portion to an adjacent one of the plurality of coil springs of the foot portion.
 6. The spring core of claim 2, wherein the flexible enclosure surrounding each of the plurality of coil springs of the middle portion is connected to the flexible enclosure of an adjacent one of the plurality of coil springs of the middle portion.
 7. The spring core of claim 2, wherein the third height is greater than the first height and the second height.
 8. The spring core of claim 7, wherein the first height and the second height are substantially the same.
 9. The spring core of claim 7, further comprising a flexible enclosure surrounding each of the plurality of coil springs of the head portion and a flexible enclosure surrounding each of the plurality of coil springs of the foot portion.
 10. The spring core of claim 9, wherein the flexible enclosure surrounding each of the plurality of coil springs of the head portion is connected to the flexible enclosure of an adjacent one of the plurality of coil springs of the head portion, and wherein the flexible enclosure surrounding each of the plurality of coil springs of the foot portion is connected to the flexible enclosure of an adjacent one of the plurality of coil springs of the foot portion.
 11. The spring core of claim 2, wherein the matrix of the middle portion defines one or more spaces between the plurality of coil springs of the middle portion, and wherein the middle portion further includes one or more interstitial springs, each of the one or more interstitial springs positioned within a respective one of the one or more spaces.
 12. The spring core of claim 11, wherein each of the one or more interstitial springs has a height greater than the third height of the plurality of coil springs of the middle portion.
 13. The spring core of claim 11, wherein each of the plurality of coil springs of the middle portion has a diameter, and wherein each of the one or more interstitial springs has a diameter smaller than the diameter of each of the plurality of coil springs of the middle portion.
 14. The spring core of claim 11, further comprising a flexible enclosure surrounding each of the plurality of coil springs of the head portion and a flexible enclosure surrounding each of the plurality of coil springs of the foot portion.
 15. A spring core for a mattress, the spring core comprising: a first section including a plurality of coil springs arranged in a matrix; and a second section including a plurality of coil springs arranged in a matrix with each of the plurality of coil springs of the second section surrounded by a flexible enclosure, the second section providing greater support, less motion transfer, or both greater support and less motion transfer than the first section.
 16. The spring core of claim 15, wherein the flexible enclosure of each of the plurality of coil springs of the second section is connected to the flexible enclosure of an adjacent one of the plurality of coil springs of the second section.
 17. The spring core of claim 15, wherein the spring core can be characterized as including a head portion, a foot portion, and a middle portion positioned between the head portion and the foot portion, wherein the first section comprises the head portion, the foot portion, or both the head portion and the foot portion, and wherein the second section comprises the middle portion.
 18. The spring core of claim 15, wherein the spring core can be characterized as including a first side portion and a second side portion opposite the first side portion, and wherein the first section comprises the first side portion and the second section comprises the second side portion.
 19. A spring core for a mattress, the spring core comprising: a plurality of coil springs arranged in a matrix, the matrix defining one or more spaces between the plurality of coil springs, and each of the plurality of coil springs surrounded by a flexible enclosure; and one or more interstitial springs, each of the one or more interstitial springs positioned within a respective one of the one or more spaces.
 20. The spring core of claim 19, wherein each of the plurality of coil springs and each of the one or more interstitial springs has a height, and wherein the height of each of the one or more interstitial springs is greater than the height of each of the plurality of coil springs.
 21. The spring core of claim 19, wherein each of the plurality of coil springs and each of the one or more interstitial springs has a diameter, and wherein the diameter of each of the one or more interstitial springs is less than the diameter of each of the plurality of coil springs. 